At least two people died and four others were injured in an explosion at Ultratec in Owens Cross Roads on Friday, Feb. 6, 2015. (Paul Gattis/pgattis@al.com)Paul Gattis | pgattis@al.com

The two women who died Friday in an explosion at Ultratec, a fireworks manufacturer in Owens Cross Roads, have been identified. Both were employees of the company.

Marie Sanderson, of Union Grove, died at the scene, according to Sgt. Brian Chaffin with the Madison County Sheriff's Office. Aimee Cothran, of Huntsville, died at Huntsville Hospital, Chaffin said.

Two other people suffered serious injuries in the explosion.

One of the injured is McKenna Whorton, daughter of State Rep. Ritchie Whorton (R-Owens Cross Roads), according to David Pinkleton, an official with the Madison County Republican Party. She was flown to the UAB Burn Center with severe burns. A man was also severely injured, and was being treated at Huntsville Hospital Friday evening.

Whorton has second-degree burns to her face and less serious burns to her hands and legs, Pinkleton said.

The explosion happened at 11:19 a.m. at the facility on Richard Brannum Drive. By 4 p.m. hazmat units had left the scene. It occurred during a mixing process during the manufacture of fireworks. Chaffin said there were no environmental concerns following an evaluation by the hazmat units.

A witness at the scene said she was 1 mile away from the facility and the explosion shook her car as she was pulling out of her driveway.

A man who lives a half-mile from the explosion scene and can see the facility from his backyard said he heard a "massive boom" that rattled his house. The man, who declined to provide his name, said he then called 9-1-1.

Among agencies that responded to the scene, according to Chaffin, were the state fire marshal, FBI and Alcohol, Tobacco & Firearms.

Witnesses say explosion incidents are not unusual at the fireworks facility. A man who lives a half-mile from the business said in the five years he's lived there he can recall at least three major incidents. AL.com reported on a fire at the location in 2010, and an explosion in 2013, though the name and spelling of the business has changed since then.

"There have been some incidents in the past," Chaffin said. "I don't have confirmed dates or what happened on those. I'm sure that will be part of the investigation we will discuss with the ATF and other agencies. That comes several days later. But we have had incidents in the past here of a similar nature."

Several HEMSI units and helicopters responded to Friday's explosion.

There are multiple small buildings at the facility but Chaffin said he did not know how many of the buildings were damaged. The building where the explosion occurred appeared to have a hole in the roof.